Details

Autor(en) / Beteiligte

• Londershausen, Michael
• Leicht, Wolfgang
• Lieb, Folker
• Moeschler, Heinrich
• Weiss, Hanns

Titel

Molecular mode of action of annonins

Ist Teil von

• Pesticide Science, 1991, Vol.33 (4), p.427-438

Ort / Verlag

London: John Wiley & Sons, Ltd

Erscheinungsjahr

1991

Quelle

Wiley-Blackwell Journals

Beschreibungen/Notizen

• Extracts of ground seeds from Annona squamosa revealed interesting insecticidal properties. By an activity‐monitored fractionation, different acetogenins, called annonins and annonacin, were determined to be the active components. The investigation of ATP‐levels (at the LT50 value) in Plutella xylostella under treatment with annonin I and antimycin A revealed values of 1.45 and 1.35 μmole g−1 fresh weight respectively, whereas insecticides primarily afecting neurotoxic targets, e.g. cyfluthrin (sodium channels; 2.25 μmole g−1 fresh weight) or parathion (acetylcholinesterase; 2.0 μmole g−1 fresh weight) did not influence the ATP‐levels significantly (control; 1.98 μmole g−1 fresh weight). Further studies on the target site of annonins revealed an inhibitory effect on the NADH‐cytochrome c‐reductase and complex I of insect mitochondria with IC50 values of 4–8 nmole mg−1 protein and 0.8 μM respectively for annonin I. Similar results were observed for the inhibition of complex I from bovine heart muscle (IC50: <0.1 μM) or Neurospora crassa cells (IC50: 0.3 μM), whereas coupling sites II or III were not afected. Furthermore, annonins did not reveal any direct inhibition of oxidative phosphorylation or uncoupling efects.